03 Suburban 5.3 Lifter Leak Down

Hey all,

I recently purchased an 03 Suburban with a 5.3. When it sits for more than 48 to 72 hours it’s got a pretty significant rattle on cold start for a split second. My guess is that 1 or more lifters are leaking down, hence the noise, until the oil pressurizes again. Start and run it every day, no noise. No noise when driving, load/no load, doesn’t matter, quiet as a church mouse.

From what I’ve been reading online here and various other forums, lifter tick is a common problem, I don’t have that, at least not sustained. And lifter leak down is considered “normal”, but this is the first vehicle I’ve owned that has displayed this particular quirk. I have driven an 02 Sierra, purchased new, for the past 17 years, no lifter noises or rattles ever, before that I had a ’95 Sierra (purchased new) and never had any engine noises from that either.

While I’m confident that the problem is lifter leak down and the most efficacious “fix” is to simply start and run it for a few minutes every day to prevent leak down and subsequent cam damage, I would like some input from the pros:

1 – Do you concur that it’s lifter leak down?
2 – Is there a way to diagnose this more accurately?
3 – Is it worth the cost of installing new lifters (approx $500 in parts)
4 – If new lifters are the ticket, what are the odds that the cam would need to be changed as well?

As I said, this is an 03 Suburban, 5.3L engine, 146K on the clock. I was told that there’s been no major engine work and no tranny work done. It is in good overall condition, just in need of some TLC, mostly minor aesthetics. I will be replacing brakes all around and new front shocks in the coming days. Other than that, she seems to have really good bones.